1. Technical Field
The technical field relates to a printing method, and specifically to a printing method of a powder-bed type 3D printer.
2. Description of Prior Art
FIG. 1 is a schematic diagram of powder-bed type 3D printer of related art. FIG. 1 discloses a powder-bed type 3D printer (refers to as 3D printer 1 hereinafter), the 3D printer 1 comprises a sprayer 11, a working plane 12 and a forming platform 13 below the working plane 12, wherein the sprayer 11 comprises an adhesive nozzle 111 for jetting adhesive and multiple color nozzles 112 for respectively jetting color-inks corresponding to different colors.
The powder-bed type 3D printing technology in the related art basically spreads a layer of powder 21 upon the forming platform 12, uses the color nozzles 112 to respectively jet different colors' inks to change the powder's color, and uses the adhesive nozzle 111 to jet adhesive to make the layer of powder 21 coheres as a formed subject 22.
Please also refer to FIG. 2, which is a schematic diagram of printing image of related art. The formed subject 22 is constituted by stacking multiple printing layers, where each printing layer is respectively corresponding to one frame of printing image I1. As shown in FIG. 2, each printing image I1 mainly comprises color information 31 which is applied to an outer contour part of the printing layer and adhesive information 32 which is applied to an internal structure part of the same printing layer. In particularly, when printing the printing layer, the 3D printer 1 controls the adhesive nozzle 111 to jet adhesive at indicated position(s) according to the adhesive information 32 of the printing image I1, and controls the color nozzles 112 to respectively jet corresponding color inks at indicated position(s) according to the color information 31 of the printing image I1.
For stablizing the formed subject 22, the adhesive is always jetted at the structure part inside the formed subject 22. On the other hand, the outer contour part of the formed subject 22 is visible, so the color inks upon the outer contour part will be chosen and jetted corresponding to the colors recorded in the original 3D module file.
As mentioned above, the 3D printer 1 only uses a little color inks when printing the contour of the formed subject 22. Accordingly, the requirement of the adhesive is much higher than that of the color inks in the printing method of related art. In other words, the utility rate of the adhesive nozzle 111 is much higher than that of the color nozzles 112.
Because the utility rate of the adhesive nozzle 111 is much higher than that of the color nozzles 112, the damage rate of the adhesive nozzle 111 is also higher than that of the color nozzles 112. Besides, for effectively narrowing the size of the 3D printer 1, some technologies in related art adopted by industries integrate the adhesive nozzle 111 and the color nozzles 112 into a single sprayer 11, and the adhesive nozzle 111 and the color nozzles 112 of the sprayer 11 cannot be disassembled alone. In this case, the entire sprayer 11 needs to be changed if the adhesive nozzle 111 is out of work, and it may discourage the users from using it.
Furthermore, the aforementioned 3D printer 1 basically adopts powder-bed type 3D printing technology, if the environment is filled of the powder 21, the sprayer 11 of the 3D printer 1 is easily obstructed by the powder 21 floating in the environment. Also, because the utility rate of the color nozzles 112 is low, if the color nozzles 112 are not controlled to jet properly to keep themselves moist, the color nozzles 112 are easily damaged due to the obstruction of the powder 21.